1. Field of the Disclosure
This disclosure relates generally to devices for use in a wellbore, specifically devices that may be utilized to control another device, wherein the output of such devices is based on content in the formation fluid flowing into the wellbore.
2. Background of the Art
Wellbores are drilled in subsurface formations for the production of hydrocarbons (oil and gas). Modern wells can extend to great well depths, often more than 15,000 ft. Hydrocarbons are trapped in various traps or zones in the subsurface formations at different depths. Such zones are referred to as reservoirs or hydrocarbon-bearing formations or production zones. To produce hydrocarbons from such zones, a completion system that typically includes a casing and a production string therein is deployed in the wellbore. The casing is perforated at spaced apart locations to allow fluid from the various production zones to enter into the casing. The production string includes a sand screen adjacent each perforated section to inhibit the flow of rock particles from the formation into the production string. Flow control devices, such as sliding sleeve valves and other devices are employed to control the flow of the fluid from the production zones into the production string. Some such devices are electrically-controlled and others are controlled by mechanical tools conveyed from the surface.
The disclosure herein provides a device that operates based on the oil and water contents in the formation fluid flowing into the wellbore, which device may be used, among other things, as a switch or as a device to operate another device, such as a sliding sleeve valve.